Impulsive gravitational waves of massless particles in extended theories of gravity

TL;DR

This paper explores specific gravitational wave solutions in extended theories of gravity, showing they often resemble or are proportional to those in general relativity, and identifies conditions for their existence.

Contribution

It provides necessary conditions for vacuum pp-wave and Aichelburg-Sexl solutions in f(R) and Gauss-Bonnet gravity, extending understanding of wave solutions in modified gravity theories.

Findings

Wave profiles are similar or proportional to general relativity.

Derived conditions for solutions in various f(R) and Gauss-Bonnet models.

Analyzed solutions with minimal and nonminimal matter couplings.

Abstract

We investigate the vacuum pp-wave and Aichelburg-Sexl-type solutions in f(R) and the modified Gauss-Bonnet theories of gravity with both minimal and nonminimal couplings between matter and geometry. In each case, we obtain the necessary condition for the theory to admit the solution and examine it for several specific models. We show that the wave profiles are the same or proportional to the general relativistic one.